MTN contracts

I am very dissatisfied, with MTN contracts department after I was notified that I owe them a month to month money for a contract I took on 2019 to 2021 October. I got myself owing them over 1k paid them sent POP to legal and accounts with a mails requesting for the account to closed down - They **** low till the money accumulated to more than 1k again without communicating with me that the account is still open - can anyone advice how can I resolve this issue without being milked dry by Mtn